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Under piston cooling oilsquirters

Practical Engine Building

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I want to fit BMW oil squirters into a 2.2 16V GM engine, however i don't know what is the best angle to drill the holes to fit the squirters. They will be fitted on the top half of the main bearings of the crankshaft. At the moment i calculated the spray angle (where they spray on) to be on the middle of the intake side of the piston when the piston is halfway its stroke. I already made a jig to drill the holes in this angle. I just want to know how you guys think about the sprayangle.

I posted some pictures so you can see what i want to do. (Not my engine)

Thanks in advance!

Attached Files

Retro-fitting under piston oil squirters isn't something I've ever considered sorry. All I can really offer is what I've seen from OE manufacturers. In some cases the oil squirters are setup to spray directly up under the piston skirt while others are angled to offer an oil spray that is directed towards the thrust side of the bore. In the perfect world you'd probably be best to direct the flow towards the exhaust side of the piston crown but the reality is probably that any oil supply is better than none. Just keep in mind that this will obviously reduce the oil supply available to the bearings.

Hello Andre,

Thank you very much for the input!

I know the oil supply will suffer, but i'm gonna use an oil pump from a newer type engine which has under piston squirters from the factory (also turbocharged), it fits 1 on 1 on my engine so i think my oil supply should be good.